1
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Nayak MK, Elvers BJ, Mehta S, Krummenacher I, Mondal A, Braunschweig H, Schulzke C, Ravat P, Jana A. Bis-[cyclic(alkyl)(amino)carbene]-derived diradicals. Chem Commun (Camb) 2024; 60:1739-1742. [PMID: 38240479 DOI: 10.1039/d3cc05779h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Crystalline polymeric structures of trans-1,4-cyclohexylene bridged N-tethered bis-CAACs in the form of their LiOTf adducts were synthesized and isolated. These were further used as building blocks for the synthesis of crystalline (amino)(carboxy)-based diradicals. The triplet diradical character of these compounds was unambiguously confirmed by the presence of a half-field signal in their EPR spectra. Theoretical calculations show that the singlet state is marginally more stable than the triplet state.
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Affiliation(s)
- Mithilesh Kumar Nayak
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500107, India.
| | - Benedict J Elvers
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489, Greifswald, Germany.
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, 560012, India.
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, 560012, India.
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489, Greifswald, Germany.
| | - Prince Ravat
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500107, India.
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2
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Nayak MK, Sarkar P, Elvers BJ, Mehta S, Zhang F, Chrysochos N, Krummenacher I, Vijayakanth T, Narayanan RS, Dolai R, Roy B, Malik V, Rawat H, Mondal A, Boomishankar R, Pati SK, Braunschweig H, Schulzke C, Ravat P, Jana A. A bis-NHC-CAAC dimer derived dicationic diradical. Chem Sci 2022; 13:12533-12539. [PMID: 36382295 PMCID: PMC9629079 DOI: 10.1039/d2sc03937k] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/21/2022] [Indexed: 08/11/2023] Open
Abstract
The isolation of carbon-centered diradicals is always challenging due to synthetic difficulties and their limited stability. Herein we report the synthesis of a trans-1,4-cyclohexylene bridged bis-NHC-CAAC dimer derived thermally stable dicationic diradical. The diradical character of this compound was confirmed by EPR spectroscopy. The variable temperature EPR study suggests the singlet state to be marginally more stable than the triplet state (2J = -5.5 cm-1 (ΔE ST = 0.065 kJ mol-1)). The presence of the trans-1,4-cyclohexylene bridge is instrumental for the successful isolation of this dicationic diradical. Notably, in the case of ethylene or propylene bridged bis-NHC-CAAC dimers, the corresponding dicationic diradicals are transient and rearrange to hydrogen abstracted products.
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Affiliation(s)
| | - Pallavi Sarkar
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research Bangalore-560064 India
| | - Benedict J Elvers
- Institut für Biochemie, Universität Greifswald Felix-Hausdorff-Straße 4 D-17489, Greifswald Germany
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit, Indian Institute of Science Bangalore 560012 India
| | - Fangyuan Zhang
- Institute of Organic Chemistry, University of Würzburg Am Hubland 97074 Würzburg Germany
| | - Nicolas Chrysochos
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500107 India
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Thangavel Vijayakanth
- Department of Chemistry, Indian Institute of Science Education and Research Pune Dr Homi Bhabha Road Pune 411008 India
| | | | - Ramapada Dolai
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500107 India
| | - Biswarup Roy
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500107 India
| | - Vishal Malik
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500107 India
| | - Hemant Rawat
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500107 India
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science Bangalore 560012 India
| | - Ramamoorthy Boomishankar
- Department of Chemistry, Indian Institute of Science Education and Research Pune Dr Homi Bhabha Road Pune 411008 India
| | - Swapan K Pati
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research Bangalore-560064 India
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald Felix-Hausdorff-Straße 4 D-17489, Greifswald Germany
| | - Prince Ravat
- Institute of Organic Chemistry, University of Würzburg Am Hubland 97074 Würzburg Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500107 India
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3
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Kumar R, Richter S, Maity S, Sarkar P, Chrysochos N, Pati SK, Ghosh P, Schulzke C, Jana A. Activation of O 2 across a C(sp 3)-C(sp 3) bond. Chem Commun (Camb) 2022; 58:3122-3125. [PMID: 35113113 DOI: 10.1039/d2cc00110a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The activation of atmospheric molecular dioxygen (O2) is reported, which occurred across a C(sp3)-C(sp3) bond of a piperazine derivative without any catalyst at ambient conditions under the formation of 1,2,4,7-dioxadiazoctane, an 8-membered (larger-ring) cyclic organic peroxide.
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Affiliation(s)
- Rahul Kumar
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
| | - Stefan Richter
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489 Greifswald, Germany.
| | - Suvendu Maity
- Department of Chemistry, Ramakrishna Mission Residential College, Narendrapur, Kolkata-700103, India.
| | - Pallavi Sarkar
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore-560064, India.
| | - Nicolas Chrysochos
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
| | - Swapan K Pati
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore-560064, India.
| | - Prasanta Ghosh
- Department of Chemistry, Ramakrishna Mission Residential College, Narendrapur, Kolkata-700103, India.
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489 Greifswald, Germany.
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
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4
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Kumar R, Chandra S, Nayak MK, Singha Hazari A, Elvers BJ, Schulzke C, Sarkar B, Jana A. An Air-Stable Alkene-Derived Organic Radical Cation. ACS OMEGA 2022; 7:837-843. [PMID: 35036750 PMCID: PMC8757455 DOI: 10.1021/acsomega.1c05479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 10/27/2021] [Indexed: 06/14/2023]
Abstract
Alkenes are known to undergo oxidation to radical cations and dications. The radical cations are often highly reactive and not stable under air. Herein, we report the synthesis, isolation, characterization, and molecular structure of an alkene-derived radical cation A, which is stable in air both in the solid state and in solution. The access to this compound was facilitated from E-diamino tri-substituted alkene B as a synthon for the synthesis of A through one-electron oxidation. The E-diamino tri-substituted alkene B was synthesized by the two-electron reduction of N,N'-1,2-propylene-bridged bis-2-phenyl-pyrrolinium cation C. Under two-electron oxidation, alkene B transforms back to cation C involving a double carbocation rearrangement.
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Affiliation(s)
- Rahul Kumar
- Tata
Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Shubhadeep Chandra
- Universität
Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische
Koordinationschemie, Institut für
Anorganische Chemie, Pfaffenwaldring 55, Stuttgart D-70569, Germany
| | - Mithilesh Kumar Nayak
- Tata
Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Arijit Singha Hazari
- Universität
Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische
Koordinationschemie, Institut für
Anorganische Chemie, Pfaffenwaldring 55, Stuttgart D-70569, Germany
| | - Benedict J. Elvers
- Institut
für Biochemie, Universität
Greifswald, Felix-Hausdorff-Straße 4, Greifswald D-17489, Germany
| | - Carola Schulzke
- Institut
für Biochemie, Universität
Greifswald, Felix-Hausdorff-Straße 4, Greifswald D-17489, Germany
| | - Biprajit Sarkar
- Universität
Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische
Koordinationschemie, Institut für
Anorganische Chemie, Pfaffenwaldring 55, Stuttgart D-70569, Germany
| | - Anukul Jana
- Tata
Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
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5
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Kundu A, Chandra S, Mandal D, Neuman NI, Mahata A, Anga S, Rawat H, Pal S, Schulzke C, Sarkar B, Chandrasekhar V, Jana A. Twisted Push-Pull Alkenes Bearing Geminal Cyclicdiamino and Difluoroaryl Substituents. J Org Chem 2021; 86:12683-12692. [PMID: 34473501 DOI: 10.1021/acs.joc.1c01201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The systematic combination of N-heterocyclic olefins (NHOs) with fluoroarenes resulted in twisted push-pull alkenes. These alkenes carry electron-donating cyclicdiamino substituents and two electron-withdrawing fluoroaryl substituents in the geminal positions. The synthetic method can be extended to a variety of substituted push-pull alkenes by varying the NHO as well as the fluoroarenes. Solid-state molecular structures of these molecules reveal a notable elongation of the central C-C bond and a twisted geometry in the alkene motif. Absorption properties were investigated with UV-vis spectroscopy. The redox properties of the twisted push-pull alkenes were probed with electrochemistry as well as UV-vis/NIR and EPR spectroelectrochemistry, while the electronic structures were computationally evaluated and validated.
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Affiliation(s)
- Abhinanda Kundu
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Shubhadeep Chandra
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Debdeep Mandal
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Nicolás I Neuman
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.,Instituto de Desarrollo Tecnológico para la Industria Química, CCT Santa Fe CONICET-UNL, Colectora Ruta Nacional 168, Paraje El Pozo, 3000 Santa Fe, Argentina
| | - Alok Mahata
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Srinivas Anga
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Hemant Rawat
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Sudip Pal
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489 Greifswald, Germany
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | | | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
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6
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Mahata A, Chrysochos N, Krummenacher I, Chandra S, Braunschweig H, Schulzke C, Sarkar B, Yildiz CB, Jana A. α,α'-Diamino- p-tetrafluoroquinodimethane: Stability of One- and Two-Electron Oxidized Species and Fixation of Molecular Oxygen. J Org Chem 2021; 86:10467-10473. [PMID: 34269573 DOI: 10.1021/acs.joc.1c01120] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Herein, we report the synthesis, characterization, and reactivity of α,α'-diamino-p-tetrafluoroquinodimethane, a p-tetrafluorophenylene-bridged monosubstituted carbene-based Thiele's hydrocarbon A. The compound exhibits a reversible two-step one-electron oxidation with a marginally stable radical cation state B. The in situ formation of the radical cation could be confirmed by electron paramagnetic resonance spectroscopy. Interestingly, α,α'-diamino-p-tetrafluoroquinodimethane fixates atmospheric oxygen to form a 16-membered peroxide-bridged macrocyclic compound C.
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Affiliation(s)
- Alok Mahata
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Nicolas Chrysochos
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489 Greifswald, Germany
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry and Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Shubhadeep Chandra
- Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry and Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489 Greifswald, Germany
| | - Biprajit Sarkar
- Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Cem B Yildiz
- Department of Medicinal and Aromatic Plants, University of Aksaray, 68100 Aksaray, Turkey
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
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7
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Mahata A, Chandra S, Maiti A, Rao DK, Yildiz CB, Sarkar B, Jana A. α,α′-Diamino-p-quinodimethanes with Three Stable Oxidation States. Org Lett 2020; 22:8332-8336. [DOI: 10.1021/acs.orglett.0c02964] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alok Mahata
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, India
| | - Shubhadeep Chandra
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Fakultät Chemie, Pfaffenwaldring 55, D-70569, Stuttgart, Germany
| | - Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, India
| | - D. Krishna Rao
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, India
| | - Cem B. Yildiz
- Department of Aromatic and Medicinal Plants, University of Aksaray, Aksaray-68100, Turkey
| | - Biprajit Sarkar
- Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Universität Stuttgart, Fakultät Chemie, Pfaffenwaldring 55, D-70569, Stuttgart, Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, India
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8
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Maiti A, Chandra S, Sarkar B, Jana A. Acyclic diaminocarbene-based Thiele, Chichibabin, and Müller hydrocarbons. Chem Sci 2020; 11:11827-11833. [PMID: 34123209 PMCID: PMC8162802 DOI: 10.1039/d0sc03622f] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Thiele, Chichibabin and Müller hydrocarbons are considered as classical Kekulé diradicaloids. Herein we report the synthesis and characterization of acyclic diaminocarbene (ADC)-based Thiele, Chichibabin, and Müller hydrocarbons. The calculated singlet–triplet energy gaps are ΔES–T = −27.96, −3.70, −0.37 kcal mol−1, respectively, and gradually decrease with the increasing length of the π-conjugated spacer (p-phenylene vs. p,p′-biphenylene vs. p,p′′-terphenylene) between the two ADC-scaffolds. In agreement with the calculations, we also experimentally observed the enhancement of paramagnetic diradical character as a function of the length of the π-conjugated spacer. ADC-based Thiele's hydrocarbon is EPR silent and exhibits very well resolved NMR spectra, whereas ADC-based Müller's hydrocarbon displays EPR signals and featureless NMR spectra at room temperature. The spacer also has a strong influence on the UV-Vis-NIR spectra of these compounds. Considering that our methodology is modular, these results provide a convenient platform for the synthesis of an electronically modified new class of carbon-centered Kekulé diradicaloids. We report the synthesis of acyclic diaminocarbene (ADC)-scaffold based Thiele, Chichibabin, and Müller hydrocarbons. Studies support that the singlet-triplet energy gap depends on the π-conjugated spacer between the ADC scaffolds.![]()
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Affiliation(s)
- Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500046 Telangana India
| | - Shubhadeep Chandra
- Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie Pfaffenwaldring 55 D-70569 Stuttgart Germany
| | - Biprajit Sarkar
- Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie Pfaffenwaldring 55 D-70569 Stuttgart Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500046 Telangana India
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9
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Mandal D, Stein F, Chandra S, Neuman NI, Sarkar P, Das S, Kundu A, Sarkar A, Rawat H, Pati SK, Chandrasekhar V, Sarkar B, Jana A. Trisubstituted geminal diazaalkene derived transient 1,2-carbodications. Chem Commun (Camb) 2020; 56:8233-8236. [PMID: 32558832 DOI: 10.1039/d0cc02807j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The coulombic repulsion between two adjacent cation centres of 1,2-carbodications is known to decrease with π- and/or n-donor substituents by a positive charge delocalization. Here we report the delocalization of the positive charge of transient 1,2-carbodications having one H-substituent by an intramolecular base-coordination. N-heterocyclic olefin (NHO) derived 2-pyrrolidinyl appended trisubstituted geminal diazaalkenes were used for the generation of transient 1,2-carbodications through a 2-e chemical oxidation process. We have also studied the 1-e oxidation reaction of trisubstituted geminal diazaalkenes (electrochemically and chemically) and also studied them using in situ EPR spectroscopy.
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Affiliation(s)
- Debdeep Mandal
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500107, Telangana, India.
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10
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Nayak MK, Stubbe J, Neuman NI, Narayanan RS, Maji S, Schulzke C, Chandrasekhar V, Sarkar B, Jana A. N,N'-Ethylene-Bridged Bis-2-Aryl-Pyrrolinium Cations to E-Diaminoalkenes: Non-Identical Stepwise Reversible Double-Redox Coupled Bond Activation Reactions. Chemistry 2020; 26:4425-4431. [PMID: 31994763 PMCID: PMC7187269 DOI: 10.1002/chem.202000255] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Indexed: 12/31/2022]
Abstract
This work presents a stepwise reversible two‐electron transfer induced hydrogen shift leading to the conversion of a bis‐pyrrolinium cation to an E‐diaminoalkene and vice versa. Remarkably, the forward and the reverse reaction, which are both reversible, follow two completely different reaction pathways. Establishing such unprecedented property in this type of processes was possible by developing a novel synthetic route towards the starting dication. All intermediates involved in both the forward and the backward reactions were comprehensively characterized by a combination of spectroscopic, crystallographic, electrochemical, spectroelectrochemical, and theoretical methods. The presented synthetic route opens up new possibilities for the generation of multi‐pyrrolinium cation scaffold‐based organic redox systems, which constitute decidedly sought‐after molecules in contemporary chemistry.
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Affiliation(s)
- Mithilesh Kumar Nayak
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad, 500107, India
| | - Jessica Stubbe
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany
| | - Nicolás I Neuman
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany.,Instituto de Desarrollo Tecnológico para la Industria Química, CCT Santa Fe CONICET-UNL, Colectora Ruta Nacional 168, Km 472, Paraje El Pozo, 3000, Santa Fe, Argentina
| | | | - Sandipan Maji
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad, 500107, India
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, 17487, Greifswald, Germany
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad, 500107, India.,Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany.,Institut für Anorganische Chemie, Lehrstuhl für Anorganische Koordinationschemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad, 500107, India
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